1. Field of Invention
The invention relates generally to systems for hoisting utilitarian devices between use and service positions and particularly to such systems wherein a luminaire or cluster of luminaires are raised and lowered between use and service positions within an indoor or similar facility.
2. Description of the Prior Art
Luminaires and other utilitarian devices are often mounted indoors in dwellings, commercial and industrial buildings and even within the confines of structures such as open-air pavilions and the like in situations wherein access to the luminaires or other devices is impeded. In such situations, maintenance and repair are difficult due to the disposition of furniture, equipment and/or machinery inter alia directly below such luminaires or similar devices obviate the use of lift devices, ladders or the like for maintenance of such devices. In domestic situations, chandeliers or similar lighting fixtures are often mounted in spaces having furnishings and the like directly below such lighting fixtures, maintenance and lamp replacement not being possible except in a lowering of such fixtures to a height enabling access to the fixture or fixtures. Similarly, commercial situations such as retail stores, warehouses and the like have display cases, elevated shelving and other equipment located below lighting fixtures and other utilitarian devices with a result that access to such devices is difficult through use of ladders and the like especially in situations wherein the devices are located at substantial heights above the floor of such spaces. Industrial situations wherein machinery including chemical processing equipment and the like are located below luminaires mounted at heights above such machinery present additional though similar problems. In all such situations, personal safety must be considered when ladders and other expedients are used that require repair or maintenance personnel to ascend to the “in use” position of the lighting fixtures or other utilitarian devices mounted at heights above floor levels.
Systems intended to address the problems inherent in maintaining luminaires and the like in situations such as are noted herein have been devised previously, one such system being available from Aladdin Light Lift Incorporated for lowering chandeliers and the like, this system having all active components thereof mounted above a ceiling. Glebe, in U.S. Pat. No. 5,556,195 discloses a motorized system for lowering a luminaire from an “in use” position at or near a ceiling of a room to a maintenance position at or near a floor immediately below the “in use” position, the system including a cable to which a luminaire is connected and which is movable by an electric motor mounted above or on a ceiling. Glebe is distinguished from the Aladdin system by the ability of the Glebe system to function without interruption of electrical power to a winch/motor used to lower and then raise the luminaire in need of maintenance, repair or replacement. Pfaff, Jr., in U.S. Pat. No. 3,610,584, similarly discloses a luminaire lowering system wherein active lowering mechanisms are located above a ceiling as does Falls et al in U.S. Pat. No. 5,105,349 and Evans in U.S. Pat. No. 5,420,772. In these systems, service of active components of the lowering systems themselves is difficult due to the location of the active components such as motors, switches and electrical and mechanical connections inter alia either in enclosed locations above ceilings or in locations difficult to access for reasons similar to inability to access luminaires or the like such as initially requires use of these lowering systems. Lowering systems of varying description are also disclosed by Sakurai in U.S. Pat. No. 4,381,539; by Mier-Langner et al in U.S. Pat. No. 6,843,581 and by Weinhuber in U.S. Pat. No. 6,758,581. The prior art as represented by the foregoing systems as disclosed in the listed patents and as practiced in the disclosed systems are configured such that active components of such lowering systems are difficult to access for maintenance and repair. Further, lowering systems of the prior art as represented by the patents and systems referred to above are not susceptible to ready retrofit in existing buildings and, in any event, are configured to be disposed in essence only above or at a ceiling of a building. Still further, the lowering systems of the prior art do not provide positive latchment of one or more luminaires such as can be mountable to a lowering box or the like so that the luminaire or luminaires are mounted with an exceptional degree of stability when disposed in the “in use” position at or near a ceiling of a building. The prior art therefore remains in need of a lowering system useful in environments as referred to herein and which yields solution to previously unaddressed or unresolved problems inherent in the use of prior lowering systems, the present invention addressing such problems in a novel lowering system for single or multiple luminaires or similar utilitarian devices as disclosed herein. The present invention further addresses the need to accommodate mechanical elements of the present lowering systems to ceiling configurations having differing angles.